you probably had measured the V+/- against the AC GND at the xfmr,before you had the connection of all grounds completed.

The right value for the input-inline-series resistor ought to be between 22 Ohm and 68 Ohm, to reduce 16V to 12V when loaded by the 150mA of the heaters, and the few mA of the plates and IC.This R should be rated at least 1W (better: 2x1W parallell with appr. values; e.g. 2x 100 Ohm).

either the tube`s filaments are broken, or connected by cold solder joints/broken wire,or the meter needs a new battery.What resistance do you measure between the naked tube`s pins4 & 5?(tube taken out of socket)What resistance do you measure (wallwart un-plugged / out of the circuit; caps discharged) between the points in your build, from where the wires to the tube-heaters origin (tube in socket, now).

Disconnected psu and caps discharged :Between the power boards 11.7 Ohm resistor and tube pin 4 I have 11.7ohms reistance.This is as close too the power board 10ohm/1 watt as i could getbetween power board AC entrance point and tube pin 4 "0" resistance

Ton,Thank you SO MUCH for going to all this trouble on my behalf, it is VERYmuch appreciated

I promise you that I am making the correct and relevent AC/DC readingsI did check that 680 Ohm resistor and a few more from that batch andcan confirm that they DO read 680 ... not 68 !!The meter is working correctly.I've gone through both boards/schems/layouts with a finr tooth comb andcan find nothing "wrong" in the values/connections ....

As I said yesterday, I have the circuit almost "working" now, the gain/tone/volume controls behave normally and the circuit is producing ahealthy amount of level ...It's just that the "cut off" and seemingly "rail to rail" stuttering continuesbut can be "fixed" by a connection from the "power board" ground, toMY SKIN ..... and whatever explination for resistance/ground that givesseems to be the answer .I realize that in comparison to your calculations for the voltage I shouldhave, it makes NO SENSE whatsoever ...! and I just dont have a reasonfor that .If I only had 1.9 volts at the tube, I'm presuming that I would not haveany "gain" nor a working "overdrive" circuit .. correct ?

I do now have approximately +12 and -12 volts where it needs to be andI have 12.3 volts at pin 4 of the tube ref to pin 5/power board groundI will try to connect the "grounds" again with some resistance, as thisseemed to solve Mark's problem, but so far, whenever I reconnect thetwo boards ground rail, I loose all signal .. not even a "hum" remains !!

I know, its wierd and the more I think about it, the more it hurts my very tiny brain

Marty.

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"Success is the ability to go from one failure to another with no loss of enthusiasm"My Website www.martinlister.com